Blacklist (issuer blacklist)
An issuer blacklist is the set of addresses that a stablecoin contract blocks from moving tokens. Circle's USDC contract has a 'blacklister' role and checks the list on transfers, for both sender and recipient, and on mints. Tether's USDT Ethereum contract keeps an isBlackListed mapping that only the owner can change. Tether's terms list 'blacklisting any Digital Tokens Address which holds Tether Tokens' among sanctions for prohibited use; Circle's terms call such addresses 'Blocked Addresses'.
What the sources say
| Source | Quote | Link |
|---|---|---|
| Circle Blacklistable.sol: role | "@dev Allows accounts to be blacklisted by a "blacklister" role" | GitHub |
| Circle FiatTokenV1.sol: transfer checks sender and recipient | "function transfer(address to, uint256 value) external virtual override whenNotPaused notBlacklisted(msg.sender) notBlacklisted(to)" | GitHub |
| Circle FiatTokenV1.sol: mint checks the list | "onlyMinters notBlacklisted(msg.sender) notBlacklisted(_to)" | GitHub |
| TetherToken source: isBlackListed mapping and owner-only change | "mapping (address => bool) public isBlackListed; function addBlackList (address _evilUser) public onlyOwner {" | Etherscan |
| Tether terms: blacklisting as a sanction | "blacklisting any Digital Tokens Address which holds Tether Tokens" | tether.to |
| Circle USDC terms: Blocked Addresses | "Circle reserves the right to “block” certain USDC addresses" | circle.com |
Related terms
See also
- Data: Stablecoin freezes and seizures by issuer
- Explainer: Which stablecoins can be frozen, and by whom?
- Review: revain.org/coins/usdt/
- Review: revain.org/coins/usdc/
- Review: revain.org/coins/gho/
- Review: revain.org/coins/dai/
Checked against the sources on 2026-11-01.
revain.org
Sources
- https://raw.githubusercontent.com/circlefin/stablecoin-evm/master/contracts/v1/Blacklistable.sol
- https://raw.githubusercontent.com/circlefin/stablecoin-evm/master/contracts/v1/FiatTokenV1.sol
- https://etherscan.io/address/0xdac17f958d2ee523a2206206994597c13d831ec7#code
- https://tether.to/en/legal/
- https://www.circle.com/legal/usdc-terms